This invention relates to lighting apparatus and method for use on operating machines and more particularly for use with textile weaving machines having an overhead air conditioning duct.
Overall machine efficiency of high-speed textile looms can be improved by the addition of direct air conditioning systems. These systems exhaust conditioned air directly to the harness area of the textile loom. Other air conditioning systems require that the entire room be conditioned in order to achieve the proper combination of humidity and temperature for optional loom operation. Systems delivering conditioned air directly to weaving machines typically require the installation of air ducts directly over the harness area. Exhaust air outlets direct the conditioned air from the duct into the area of the loom where the weaving operation takes place.
These overhead ducts produce shadows on the weaving machines due to their blockage of light from conventional ceiling mounted illumination sources. The installation of a traditional fluorescent fixture or luminaire with the usual symmetrical light distribution pattern alongside the duct, will illuminate one side of the machine, typically the weave side, at the expense of the other side of the machine, the warp side. Also, a portion of the light will fall onto aisle and floor areas, resulting in inefficiency by reason of lost light.
The prior art is exemplified by the LOOMSPHERE air conditioning system by Luwa Bahanson, Inc. of Zurich, Switzerland and Winston-Salem, N.C. Features of the air conditioning system are illustrated in U.S. Pat. No. 5,666,966 where it will be noted that the elongated horizontal ducts are supported by columns longitudinally spaced in aisles between looms. Conditioned air is directed downwardly on the looms from whence the air is received in exhaust ducts carried beneath the weaving machines under the floor of the mill for return to air conditioning apparatus. Thus, the areas between the columns is free of obstructions which may interfere with operation and servicing of the weaving machines.
The problem of shading of parts of the weaving machines from conventional fluorescent light by blockage by overhead ducts has persisted despite efforts to solve the problem. U.S. Pat. No. 5,666,966 illustrates an attempt to solve the problem by positioning a conventional lighting fixture directly beneath the air channel and positioning the outlet box to one side. This attempted solution has resulted in disadvantages including the extra expense of the ducts and air channels. Inefficiencies result because of pressure drops occurring in the more extensive duct work of the proposed system.